This invention pertains to irrigation devices capable of varying their irrigation patterns. The invention particularly relates to those which achieve the desired patterns through the circular motion of an irrigation jet, whose range is controlled by varying its angle of elevation as illustrated in U.S. Pat. Nos. 2,979,271 and 3,091,399. The above mentioned references describe apparatus which respectively utilize nonadjustable cylindrical cams and flat interchangeable cam plates to position the nozzle's angle of elevation as the device is caused to rotate circularly by internal mechanisms. The disclosed apparatus of the references utilize part of the kinetic energy in the water and transforms it into the mechanical energy need to provide the necessary rotation. In addition to the introduction of an adjustable contour plate to perform the functions said cylindrical cams and cam plates, in the present invention all internal mechanisms have been eliminated, a minimal number of parts are required and uniform water distribution is closely achieved. Also pertinent is U.S. Pat. No. 3,960,327 which attempts to provide an adjustable contour surface through use of a flexible or elastomeric material frictionally engaged between an annular channel.